[U-Boot] [PATCH 3/9] arc: add library functions

Alexey Brodkin Alexey.Brodkin at synopsys.com
Wed Jan 29 00:09:34 CET 2014


Signed-off-by: Alexey Brodkin <abrodkin at synopsys.com>

Cc: Mischa Jonker <mjonker at synopsys.com>
Cc: Francois Bedard <fbedard at synopsys.com>
---
 arch/arc/lib/Makefile   |   9 ++++
 arch/arc/lib/bootm.c    | 106 ++++++++++++++++++++++++++++++++++++++++++++++++
 arch/arc/lib/relocate.c |  74 +++++++++++++++++++++++++++++++++
 arch/arc/lib/sections.c |  21 ++++++++++
 4 files changed, 210 insertions(+)
 create mode 100644 arch/arc/lib/Makefile
 create mode 100644 arch/arc/lib/bootm.c
 create mode 100644 arch/arc/lib/relocate.c
 create mode 100644 arch/arc/lib/sections.c

diff --git a/arch/arc/lib/Makefile b/arch/arc/lib/Makefile
new file mode 100644
index 0000000..6420cf2
--- /dev/null
+++ b/arch/arc/lib/Makefile
@@ -0,0 +1,9 @@
+#
+# Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y += sections.o
+obj-y += relocate.o
+obj-$(CONFIG_CMD_BOOTM) += bootm.o
diff --git a/arch/arc/lib/bootm.c b/arch/arc/lib/bootm.c
new file mode 100644
index 0000000..d185a50
--- /dev/null
+++ b/arch/arc/lib/bootm.c
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static ulong get_sp(void)
+{
+	ulong ret;
+
+	asm("mov %0, sp" : "=r"(ret) : );
+	return ret;
+}
+
+void arch_lmb_reserve(struct lmb *lmb)
+{
+	ulong sp;
+
+	/*
+	 * Booting a (Linux) kernel image
+	 *
+	 * Allocate space for command line and board info - the
+	 * address should be as high as possible within the reach of
+	 * the kernel (see CONFIG_SYS_BOOTMAPSZ settings), but in unused
+	 * memory, which means far enough below the current stack
+	 * pointer.
+	 */
+	sp = get_sp();
+	debug("## Current stack ends at 0x%08lx ", sp);
+
+	/* adjust sp by 4K to be safe */
+	sp -= 4096;
+	lmb_reserve(lmb, sp, (CONFIG_SYS_SDRAM_BASE + gd->ram_size - sp));
+}
+
+static int cleanup_before_linux(void)
+{
+	disable_interrupts();
+	flush_dcache_all();
+	invalidate_icache_all();
+
+	return 0;
+}
+
+/* Subcommand: PREP */
+static void boot_prep_linux(bootm_headers_t *images)
+{
+	if (image_setup_linux(images))
+		hang();
+}
+
+/* Subcommand: GO */
+static void boot_jump_linux(bootm_headers_t *images, int flag)
+{
+	void (*kernel_entry)(int zero, int arch, uint params);
+	unsigned int r0, r2;
+	int fake = (flag & BOOTM_STATE_OS_FAKE_GO);
+
+	kernel_entry = (void (*)(int, int, uint))images->ep;
+
+	debug("## Transferring control to Linux (at address %08lx)...\n",
+	      (ulong) kernel_entry);
+	bootstage_mark(BOOTSTAGE_ID_RUN_OS);
+
+	printf("\nStarting kernel ...%s\n\n", fake ?
+	       "(fake run for tracing)" : "");
+	bootstage_mark_name(BOOTSTAGE_ID_BOOTM_HANDOFF, "start_kernel");
+
+	cleanup_before_linux();
+
+	if (IMAGE_ENABLE_OF_LIBFDT && images->ft_len) {
+		r0 = 2;
+		r2 = (unsigned int)images->ft_addr;
+	} else {
+		r0 = 1;
+		r2 = (unsigned int)getenv("bootargs");
+	}
+
+	if (!fake)
+		kernel_entry(r0, 0, r2);
+}
+
+int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images)
+{
+	/* No need for those on ARC */
+	if ((flag & BOOTM_STATE_OS_BD_T) || (flag & BOOTM_STATE_OS_CMDLINE))
+		return -1;
+
+	if (flag & BOOTM_STATE_OS_PREP) {
+		boot_prep_linux(images);
+		return 0;
+	}
+
+	if (flag & (BOOTM_STATE_OS_GO | BOOTM_STATE_OS_FAKE_GO)) {
+		boot_jump_linux(images, flag);
+		return 0;
+	}
+
+	boot_prep_linux(images);
+	boot_jump_linux(images, flag);
+	return 0;
+}
diff --git a/arch/arc/lib/relocate.c b/arch/arc/lib/relocate.c
new file mode 100644
index 0000000..710b792
--- /dev/null
+++ b/arch/arc/lib/relocate.c
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <elf.h>
+#include <asm/sections.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+extern char __text_end[];
+
+/*
+ * Base functionality is taken from x86 version with added ARC-specifics
+ */
+int do_elf_reloc_fixups(void)
+{
+	Elf32_Rela *re_src = (Elf32_Rela *)(&__rel_dyn_start);
+	Elf32_Rela *re_end = (Elf32_Rela *)(&__rel_dyn_end);
+
+	Elf32_Addr *offset_ptr_rom, *last_offset = NULL;
+	Elf32_Addr *offset_ptr_ram;
+
+	do {
+		/* Get the location from the relocation entry */
+		offset_ptr_rom = (Elf32_Addr *)re_src->r_offset;
+
+		/* Check that the location of the relocation is in .text */
+		if (offset_ptr_rom >= (Elf32_Addr *)CONFIG_SYS_TEXT_BASE &&
+		    offset_ptr_rom > last_offset) {
+			unsigned int val;
+			/* Switch to the in-RAM version */
+			offset_ptr_ram = (Elf32_Addr *)((ulong)offset_ptr_rom +
+							gd->reloc_off);
+
+			/*
+			 * Use "memcpy" because target location might be
+			 * 16-bit aligned on ARC so we may need to read
+			 * byte-by-byte. On attempt to read entire word by
+			 * CPU throws an exception
+			 */
+			memcpy(&val, offset_ptr_ram, sizeof(int));
+
+			/* If location in ".text" section swap value */
+			if ((unsigned int)offset_ptr_rom <
+			    (unsigned int)&__text_end)
+				val = (val << 16) | (val >> 16);
+
+			/* Check that the target points into .text */
+			if (val >= CONFIG_SYS_TEXT_BASE && val <=
+			    (unsigned int)&__bss_end) {
+				val += gd->reloc_off;
+				/* If location in ".text" section swap value */
+				if ((unsigned int)offset_ptr_rom <
+				    (unsigned int)&__text_end)
+					val = (val << 16) | (val >> 16);
+				memcpy(offset_ptr_ram, &val, sizeof(int));
+			} else {
+				debug("   %p: rom reloc %x, ram %p, value %x, limit %x\n",
+				      re_src, re_src->r_offset, offset_ptr_ram,
+				      val, (unsigned int)&__bss_end);
+			}
+		} else {
+			debug("   %p: rom reloc %x, last %p\n", re_src,
+			      re_src->r_offset, last_offset);
+		}
+		last_offset = offset_ptr_rom;
+
+	} while (++re_src < re_end);
+
+	return 0;
+}
diff --git a/arch/arc/lib/sections.c b/arch/arc/lib/sections.c
new file mode 100644
index 0000000..b0b46a4
--- /dev/null
+++ b/arch/arc/lib/sections.c
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+/*
+ * For some reason linker sets linker-generated symbols to zero in PIE mode.
+ * A work-around is substitution of linker-generated symbols with
+ * compiler-generated symbols which are properly handled by linker in PAE mode.
+ */
+
+char __bss_start[0] __attribute__((section(".__bss_start")));
+char __bss_end[0] __attribute__((section(".__bss_end")));
+char __image_copy_start[0] __attribute__((section(".__image_copy_start")));
+char __image_copy_end[0] __attribute__((section(".__image_copy_end")));
+char __rel_dyn_start[0] __attribute__((section(".__rel_dyn_start")));
+char __rel_dyn_end[0] __attribute__((section(".__rel_dyn_end")));
+char __text_start[0] __attribute__((section(".__text_start")));
+char __text_end[0] __attribute__((section(".__text_end")));
+char __init_end[0] __attribute__((section(".__init_end")));
-- 
1.8.5.3



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